1. Field of the Invention
The invention relates to the dilution of a liquid sample with a second liquid in which the sample or component thereof is soluble. The quantitative mixing of a liquid sample with a solvent is required in a number of different areas including chromatography and assays.
The field of competitive protein binding assays or specific binding assays has greatly expanded, as its importance in the diagnostic field has become recognized. The ability to be able to detect a specific compound and measure the compound quantitatively has permitted the monitoring of the administration of a wide variety of drugs, the determination of an imbalance in a wide variety of hormones, the quantitation of physiologically active proteins, and the diagnosis of the presence of a pathogen.
In developing an assay, there are a number of considerations in devising the reagents and protocol. One consideration is the degree of sophistication of the individual performing the assay. There are many situations where it is desirable to have a relatively untrained individual carry out an assay and obtain reasonably quantitative results. It is particularly desirable that the relatively untrained individual be able to carry out a quantitative assay is a simple, rapid test without the need for sophisticated equipment. A critical element for carrying out a quantitative assay on a liquid sample is the collection and quantitative dilution of the liquid sample to be assayed.
2. Description of the Prior Art
An apparatus for precise mutual dilution and dosage of liquids is disclosed in U.S. Pat. No. 4,237,094. An adjustable diluting device is disclosed in U.S. Pat. No. 4,128,009. A plural piston, adjustable diluting device having a volume indicator assembly is described in U.S. Pat. No. 4,141,250.